Butler returned to the starting XV in the 22-16 win against Connacht at the end of 2013 but he was in injury trouble again shortly afterwards when he suffered a spinal concussion while playing for Shannon in Blackrock and missed another four games.
He's expected to feature at Thomond Park on Saturday night and Butler is keen to make up for lost time on the sidelines.
He said: "I'm delighted to be back. It's been a frustrating year out through injury so I'm absolutely delighted to get the opportunity to play again for my province. I've been out for a while so I'm very excited to be playing with Munster again."
The back-row forward has played a number of games for Shannon to regain match fitness and also started for Munster A in the Interprovincial against Connacht Eagles two weeks ago and the Tipperary man is glad to be back fit.
"When I was injured I had a fairly strict and tough regime with the strength and conditioning lads," said Butler.
"When I was coming closer to getting back playing games I played with Shannon and it was brilliant. It's a great stepping stone to be able to play with your club at a high level and then come in and get your opportunity to play with Munster again."
Paul O'Connell attended Tuesday's training session in UL after leading Ireland to the Six Nations title in Paris. Like everyone else in the country, Butler was cheering on the Irish team last weekend and he was full of praise for the national side.
"It was brilliant, the lads are on an all-time high. Representing your country and winning the Six Nations is an unbelievable achievement and it's brilliant to have Paul and the lads in the squad.
"Paulie is already back in and around the Munster squad and it's brilliant - he's a credit to himself and his club and it's great to have him around."
Munster face Treviso at Thomond Park on Saturday at 7:15pm with tickets available here.